Tea Drinking Improves Health, Study Shows

Sipping chai at College soirees may help with social skills, saucer balancing and making conversation—but it may also may help boost the immune system, according to a Harvard study published in the Proceedings of the National Academy of Sciences Monday.

The study, authored by a team of researchers led by Assistant Clinical Professor of Medicine Jack F. Bukowski of Brigham and Women’s Hospital, found a chemical in tea that boosts the body’s disease-fighting immune response.

Bukowski, an immunologist who studies rare gamma-delta T-cells, found that these cells specifically recognize molecules produced by bacteria.

These bacterial molecules prompt the cells to release a protein called interferon, which alerts the immune system to possible microbial invaders. A precursor of these molecules is found in tea.

Thus, the tea may jump-start the body’s immune response even in the absence of bacteria.

After isolating the immune-boosting chemical from tea leaves and observing the increased activity of the disease-fighting T-cells against bacteria, Bukowski took his hypothesis to human volunteers.

Some subjects drank five cups of tea a day and others drank five cups of coffee a day for four weeks.

The immune cells in the tea-drinking volunteers produced five times more interferon than the cells of the same subjects before the trial. The coffee-drinkers’ blood showed no difference in immune response.

Justin Morrison, a tea expert behind the counter at Tealuxe in Harvard Square, said he was not impressed by the findings.

“The amount of benefit it has is already overwhelming, so this is not surprising,” he said, citing the beneficial antioxidant properties of tea such as the muscle-relaxant, body cleansing and appetite suppression properties of some varieties.

Bukowski said he wants to increase the number of people in the study to make it more definitive.

“We need to take a lot of people, maybe 10,000, and split them into two groups, one coffee and one tea, both groups of people who don’t normally drink coffee or tea, and follow them year after year and record all aspects of their health—a longitudinal study,” Bukowski said.

Bukowski said he drinks about five cups of iced tea a day, and it keeps him healthy.

Bukowski said medicines are now being developed based on the mechanism of the immune-boosting properties found in tea.

But Bukowski said tea should not be used as actual therapy or treatment for disease.

“If you’re sick enough to go to the doctor, tea is not going to help,” he said.